This is an application for a 5-year renewal of an institutional training grant in the Epidemiology and Biostatistics of Aging, funded by NIA since 1996. This multidisciplinary training program's goals are to train outstanding predoctoral and postdoctoral candidates to lead the next generation of quantitative research scientists addressing the health problems of our aging population. This program is conducted jointly by epidemiologists and biostatisticians with a strong commitment to bringing together students in both disciplines to develop expertise in both the content areas and methodologies that are essential to the further development of the field. Students are trained as researchers who can conduct leading-edge descriptive, analytic and experimental studies and develop, implement and evaluate prevention programs to compress the morbidity experience of the aging population. The program is based in the Departments of Epidemiology and Biostatistics, but involves faculty from other departments throughout the Schools of Public Health, Medicine, and Nursing. A Program Director in Epidemiology, a Co-Director from Biostatistics, 5 Associate Directors from the two Departments, and 21 other core faculty members will serve as Advisors for the trainees. There is a core curriculum expected of predoctoral trainees, and customized to postdoctoral trainees. Trainees, half Epidemiology and half from Biostatistics, participate in biweekly research in progress conferences, seminars on aging, and practica specific to this program, and training dedicated to skills in multidisciplinary collaboration. Research experiences and mentors are selected to ensure high quality research worthy of peer-reviewed publication in aging research. We propose to continue to train students in epidemiologic and biostatistical method, and their application to important questions in the health status of older adults, including causes and consequences of chronic diseases, comorbidity, and disability. Students develop expertise in design and conduct of large-scale observational prospective studies;longitudinal data analysis;the genetic and molecular causes of age-related changes;the phenotype, consequences and etiology of frailty, and cognitive decline;statistical methods for the measurement and analysis of complex geriatric outcomes, such as frailty and disability;the social epidemiology of aging;and programs that translate research findings into effective prevention for older adults. We now propose to enrich and expand the emphases to include study in the design and conduct of clinical trials in older populations and the integration of physiology into longitudinal epidemiologic studies of the progression of health and disease. Trainees have been highly productive, gained substantial recognition for their research, and launched their careers in appealing positions with emphases on aging. Graduates will be effective leaders of multidisciplinary research teams tackling the health problems associated with the aging US population.